This invention relates to Fusarium avenaceum, to a method for its production, and to its use as a herbicide for Rubus species.
The discovery and development of potential biological control agents to suppress competing forest vegetation is receiving increased attention in the management of conifer regeneration sites. Development of alternatives to commonly used weed control methods, such as herbicide applications and manual cutting, has become important in forest management plans due to economical constraints and increasing public concern over pesticide use. Biological control strategies which utilize microbial organisms or their secondary metabolites to control weeds have been widely investigated on agricultural crops. In forest renewal sites, biological control agents need to be sufficiently virulent to suppress competing vegetation that is often diverse in growth habit and density, while allowing for vegetation to resume its role in forest ecosystems once conifer release has been obtained.
Invasive Rubus species, namely wild red raspberry [Rubus strigosus Michx.=R. idaeus var. strigosus (Michx.) Focke], thimbleberry (R. parviflorus Nutt.), and salmonberry (R. spectabilis Pursh), are among the top 20 forest weeds in Canada. These native Rubus species can effectively outcompete newly planted or naturally regenerated conifers in reforestation sites in Canada and the northern United States, and reduce the growth and survival of black and white spruce. These Rubus species are perennial, deciduous shrubs which form monospecific, multi-layered shrub communities with long-lived clonal root systems.